NAME

systat - display system statistics on a CRT

SYNOPSIS

systat [-n] [-wwait] [display] [refresh-interval]

DESCRIPTION

systat displays various system statistics in a screen oriented fashion
using the curses screen display library, curses(3).
While systat is running the screen is usually divided into two windows
(an exception is the vmstat display which uses the entire screen). The
upper window depicts the current system load average. The information
displayed in the lower window may vary, depending on user commands. The
last line on the screen is reserved for user input and error messages.
By default systat displays the processes getting the largest percentage
of the processor in the lower window. Other displays show swap space
usage, disk I/O statistics (a la iostat(8)), virtual memory statistics (a
la vmstat(8)), network "mbuf" utilization, and network connections (a la
netstat(1)).
Input is interpreted at two different levels. A "global" command inter-
preter processes all keyboard input. If this command interpreter fails to
recognize a command, the input line is passed to a per-display command
interpreter. This allows each display to have certain display-specific
commands.
The options are as follows:
-n Do not try to reverse-map IP address.
-wwait Specifies the screen refresh time interval in seconds.
This option is overridden by refresh-interval, if
given. The default interval is 5 seconds.
display The display argument expects to be one of: pigs,
iostat, swap, mbufs, vmstat, ifstat or netstat. These
displays can also be requested interactively and are
described in full detail below.
refresh-interval The refresh-interval specifies the screen refresh time
interval in seconds. This is provided for backwards
compatibility, and overrides the wait interval speci-
fied with the -w flag. The default interval is 5
seconds.
Certain characters cause immediate action by systat. These are
^L Refresh the screen.
^G Print the name of the current "display" being shown in the
lower window and the refresh interval.
^Z Suspend systat.
: Move the cursor to the command line and interpret the input
line typed as a command. While entering a command the current
character erase, word erase, and line kill characters may be
used.
The following commands are interpreted by the "global" command inter-
preter.
help Print the names of the available displays on the command
line.
load Print the load average over the past 1, 5, and 15 minutes on
the command line.
stop Stop refreshing the screen.
[start] [number]
Start (continue) refreshing the screen. If a second, numeric,
argument is provided it is interpreted as a refresh interval
(in seconds). Supplying only a number will set the refresh
interval to this value.
quit Exit systat. (This may be abbreviated to q.)
The available displays are:
pigs Display, in the lower window, those processes resident in
main memory and getting the largest portion of the processor
(the default display). When less than 100% of the processor
is scheduled to user processes, the remaining time is ac-
counted to the "idle" process.
iostat Display, in the lower window, statistics about processor use
and disk throughput. Statistics on processor use appear as
bar graphs of the amount of time executing in user mode
("user"), in user mode running low priority processes
("nice"), in system mode ("system"), and idle ("idle").
Statistics on disk throughput show, for each drive, kilobytes
of data transferred, number of disk transactions performed,
and time spent in disk accesses (in milliseconds). This in-
formation may be displayed as bar graphs or as rows of
numbers which scroll downward. Bar graphs are shown by de-
fault.
The following commands are specific to the iostat display;
the minimum unambiguous prefix may be supplied.
numbers Show the disk I/O statistics in numeric form.
Values are displayed in numeric columns which
scroll downward.
bars Show the disk I/O statistics in bar graph form
(default).
secs Toggle the display of time in disk activity (the
default is to not display time).
split Toggle the display of separate read/write statis-
tics (the default is combined statistics).
swap Show information about swap space usage on all the swap areas
compiled into the kernel. The first column is the device name
of the partition. The next column is the total space avail-
able in the partition. The Used column indicates the total
blocks used so far; the graph shows the percentage of space
in use on each partition. If there is more than one swap par-
tition in use, a total line is also shown. Areas known to the
kernel but not in use are shown as not available.
mbufs Display, in the lower window, the number of mbufs allocated
for particular uses, i.e., data, socket structures, etc.
vmstat Take over the entire display and show a (rather crowded) com-
pendium of statistics related to virtual memory usage, pro-
cess scheduling, device interrupts, system name translation
caching, disk I/O etc.
The upper left quadrant of the screen shows the number of
users logged in and the load average over the last 1, 5, and
15 minute intervals. Below this line are statistics on memory
utilization. The first row of the table reports memory usage
only among active processes, that is, processes that have run
in the previous twenty seconds. The second row reports on
memory usage of all processes. The first column reports on
the number of physical pages claimed by processes. The second
column reports the same figure for virtual pages, that is,
the number of pages that would be needed if all processes had
all of their pages. Finally, the last column shows the number
of physical pages on the free list.
Below the memory display is a list of the average number of
processes (over the last refresh interval) that are runnable
('r'), in disk wait other than paging ('d'), sleeping ('s'),
and swapped out but desiring to run ('w'). Below the queue
length listing is a numerical listing and a bar graph showing
the amount of system (shown as '='), user (shown as '>'),
nice (shown as '-'), and idle time (shown as ' ').
To the right of the Proc display are statistics about Context
switches ("Csw"), Traps ("Trp"), Syscalls ("Sys"), Interrupts
("Int"), Soft interrupts ("Sof"), and Faults ("Flt") which
have occurred during the last refresh interval.
Below the CPU Usage graph are statistics on name transla-
tions. It lists the number of names translated in the previ-
ous interval, the number and percentage of the translations
that were handled by the system wide name translation cache,
and the number and percentage of the translations that were
handled by the per process name translation cache.
At the bottom left is the disk usage display. It reports the
number of seeks, transfers, number of kilobyte blocks
transferred per second averaged over the refresh period of
the display (by default, five seconds), and the time spent in
disk accesses.
Under the date in the upper right hand quadrant are statis-
tics on paging and swapping activity. The first two columns
report the average number of pages brought in and out per
second over the last refresh interval due to page faults and
the paging daemon. The third and fourth columns report the
average number of pages brought in and out per second over
the last refresh interval due to swap requests initiated by
the scheduler. The first row of the display shows the average
number of disk transfers per second over the last refresh in-
terval. The second row of the display shows the average
number of pages transferred per second over the last refresh
interval.
Running down the right hand side of the display is a break-
down of the interrupts being handled by the system. At the
top of the list is the total interrupts per second over the
time interval. The rest of the column breaks down the total
on a device by device basis. Only devices that have inter-
rupted at least once since boot time are shown.
Below the SWAPPING display and slightly to the left of the
Interrupts display is a list of virtual memory statistics.
The abbreviations are:
forks process forks
fkppw forks where parent waits
fksvm forks where vmspace is shared
pwait fault had to wait on a page
relck fault relock called
rlkok fault relock is successful
noram faults out of ram
ndcpy number of times fault clears "need copy"
fltcp number of times fault promotes with copy
zfod fault promotes with zerofill
cow number of times fault anon cow
fmin min number of free pages
ftarg target number of free pages
itarg target number of inactive pages
wired wired pages
pdfre pages daemon freed since boot
pdscn pages daemon scanned since boot
The '%zfod' value is more interesting when observed over a
long period, such as from boot time (see the boot option
below).
ifstat Display, in the lower window, interface statistics. See below
for more options.
netstat Display, in the lower window, network connections. By de-
fault, network servers awaiting requests are not displayed.
Each address is displayed in the format "host.port", with
each shown symbolically, when possible. It is possible to
have addresses displayed numerically, limit the display to a
set of ports, hosts, and/or protocols (the minimum unambigu-
ous prefix may be supplied):
all Toggle the displaying of server processes
awaiting requests (this is the equivalent of
the -a flag to netstat(1)).
numbers Display network addresses numerically.
names Display network addresses symbolically.
protocol Display only network connections using the in-
dicated protocol (currently either "tcp" or
"udp").
ignore [items]
Do not display information about connections
associated with the specified hosts or ports.
Hosts and ports may be specified by name
("vangogh", "ftp"), or numerically. Host ad-
dresses use the Internet dot notation
("128.32.0.9"). Multiple items may be specified
with a single command by separating them with
spaces.
display [items]
Display information about the connections asso-
ciated with the specified hosts or ports. As
for ignore, items may be names or numbers.
show [ports|hosts]
Show, on the command line, the currently
selected protocols, hosts, and ports. Hosts and
ports which are being ignored are prefixed with
a '!'. If ports or hosts is supplied as an ar-
gument to show, then only the requested infor-
mation will be displayed.
reset Reset the port, host, and protocol matching
mechanisms to the default (any protocol, port,
or host).
The following commands are specific to the vmstat and ifstat displays;
the minimum unambiguous prefix may be supplied.
boot Display cumulative statistics since the system was booted.
run Display statistics as a running total from the point this command
is given.
time Display statistics averaged over the refresh interval (the de-
fault).
zero Reset running statistics to zero.
Commands to switch between displays may be abbreviated to the minimum
unambiguous prefix; for example, "io" for "iostat". Certain information
may be discarded when the screen size is insufficient for display. For
example, on a machine with 10 drives the iostat bar graph displays only 3
drives on a 24 line terminal. When a bar graph would overflow the allot-
ted screen space it is truncated and the actual value is printed "over
top" of the bar.
The following commands are common to each display which shows information
about disk drives. These commands are used to select a set of drives to
report on, should your system have more drives configured than can nor-
mally be displayed on the screen.
ignore [drives] Do not display information about the drives indi-
cated. Multiple drives may be specified, separat-
ed by spaces.
display [drives] Display information about the drives indicated.
Multiple drives may be specified, separated by
spaces.

FILES

SEE ALSO

HISTORY

The systat program appeared in 4.3BSD.

BUGS

Takes 2-10 percent of the CPU. Certain displays presume a minimum of 80
characters per line. The vmstat display looks out of place because it is
(it was added in as a separate display rather than created as a new pro-
gram).
MirOS BSD #10-current December 30, 1993 4